Superheater for steam-boilers.



E. H. FOSTER.

SUPERHE'ATER roa STEAM BOILERS.

APPLICATIOM FILED 8.17.1916.

atented Jul 9, 1918.

3 SHEETS-SHEET l.

E. H. FOSTER. SUPERHEATER FOR STEAM BOILERS.

APPUCATION FILEDFEB. :7, I916.

\ PatntedJuly' 9, 1918.

3 SHEETS-SHEET 2.

3 wuawtoz Dongan Hills, Richmond'county, and

oasis ERNEST H. rosrnn, or when? HILLS, mzwronx; asszenon TO rowaa srsommr cOMPANY, on NEW YQRK, N. z, a CORPORATION or NEW YQBK.

SUPERHEATER FUR STEAM-BQI LERS.

To all whom "it may concern:

Be it known that I, EaNm'T citizen of the United States, residm H, Fos'rsu, a

at tato of New York,-have invented certain new and useful Improvements in Superheaters for Steam-Boilers, of which the following is a full, clear, and exact description.

The invention for which I hereby present specification and claims in connection. withv this application for LettersPatent resides in a superheater for that special type of steam boiler known as a return tubular boiler.

In such boilers the hot gases from the fire pass longitudinally under the shell of the boiler from front to rear and thence upv through a combustion chamber and forwar through the tubes of the boiler on their way to the flue. To equi such a boiler with a superheater I have ound it very desirable from the standpoint of economy and other reasons which will more fully hereinafter appear, to'devise a special form of superheater, to support the same in an entirely new way, and to employ in connection therewith certain devices which, so far as I am aware, have not heretofore been used in such systems. Generally stated my improvements are as follows: I

The superheater is contained-within the combustion chamber at the rear of the boiler proper. It consists, in part, of vertical tubes supported at their upper ends above the chamber and outside of the same, and which enter the said chamber through covers which may either be fixed to the walls of the chamber andpermit the supporting superheater tubes to move through them as the latter expand or contract, or which maybe carried by and attached to said tubes so as to move bodily as such expansion or contraction takes place. At the lower ends the superheating tubes connect with headers which are spanned by a plurality of inverted U- tubes, and drainage tubes are taken' ofi' from such headers through suitable'open ngs pro vided for them in the walls of the furnace setting.

As the hot gases in this improved arrangement enter the bottom of the combustion chamber they pass up overthe superheater and as some portion of such gases have not, up to this point, come in actual contact with the boiler heating surface, a high and uni- Specification of Letters Patent.

Patented July 9, 1918 Application filed February 17, 1918. Serial No. 78,800.

2 trated the specific construction. of a boiler of the above described type and of my improved superheater sofar as it is necessary to convey to those skilled in the'art a full understanding of the nature and purpose" of the invention.

Figure 1 is a part sectional and side view of the rear of a bdiler showing the improved superheater applied thereto. The section on which this figure is taken is illustrated by the line caa of Fig. 2.

' Fig. 2 is part section and rear elevation of the device of Fig. 1 on the line 1 of that figure.

Fig. 3 is a top plane view of the parts shown in Fig, 1, and

Fig. 4 is a section view, looking down on v the line z---2 of Fig. 2.

A is a return tubular boiler under which i is the usual passage for hot gases B, communicating through the opening C with the combustion chamber D at the rear. Above this chamber there are placed Lbeams E to afi'ord a support for the superheater.

The latter is placed within the combustiou chambefiand comprises the vertical tubes F, F, not connected, one parallel pair at each end of the'chamber, the upper ends of which are secured to and supported by" the beams E by flanges or heads or in any suitable manner. The forward pair of tubes F are connected by pipes G with the steam dome of the boiler, and the rear pair by pipes H with the throttle orits equivalent in the usual manner.

The lower ends of tubes F connect with and support headers I, which, in turn. are spanned by and carry a plurality of inverted U-tubes J. Drainage tubes M lead from the headers out through the furnace wall.

The tubes F and J all of which constitute portions of the heating surface of the super heater are shown as covered with rings or corrugations of cast iron, resembling in this respect the superheatcrs habitually made under a former-patent granted to me, and now Well known articles of comn'ierce. The rings on the vertical supporting tubes F 8X1 tend up to the covers L, which are metal plates covered with any suitable refractory material, preferably loosely fitting the openings at the sides of'the combustion chamber through which the tubes F enter.

The covers rest upon flanges or the top of the rings K surrounding the tubes F and move freely, upon and down as the said pipes expand or contract under varying temperature. ,In this Way I obtain 2i freely sup ported superheatcr which has no direct connection with the boiler, but which is free to expand or contract, and which may be bodily removed Without diliiculty, should occasion arise for such removal.

For boilers of this type this superheater is-most efficient and useful. A high and substantially uniform heat secured with a superheater of relatively small size, and in case of need, all parts of the same are easily accessible and removable.

What I claim is:

1. A. super-heater for horizontal return tubular boilers, located in the combustion chamberat the rear of the boiler, comprising in combination with tubes forming part of the heating: surface of the super-heater secured at their upper ends outside the chamber, means for permitting said tubes to expand and contract Where they pass through the arch of the combustion chamber, and

headers and superheater tubes supported by the lower ends of said tubes.

Learners with a comend having us coinbina- 2. A boiler setting provided bustion chamber n the rear openings in the arch thereof,

tion with a superheater proper located in 40 said chamber in the direct path of a portion of the furnace gases, and means for suspending said superheater proper in said chamber comprising inlet and outlet tubes for the superheater projecting through said arch openings and supported outside said heating chamber, and closures between the Walls of the openrngs the supporting tubes free to move in and out as the tube expands and contracts under the influence of the heat.

v 3. A. superheater for horizontal return tubular boilers located in the combustion chamber at th\ rear of the boiler, comprising inlet and outlet headers located Within supporting the same and for conveying the saturated steam to and superheated steam,

from said headers, said inlet and outlet tubes pasing through openings in the top of the boiler setting, and covers for said openings through which said tubes pass". into said chamber, said covers adapted to move upwardly and downwardly in said openings with said tubes as-the latter contract and expend,

In testimony whereof I hereuntoailix my signature.

runner n. rosrnn. 

